Abstract
In this study, Hydrus-1D model was used to simulate the evaporation from the soil surface for different wetting intervals for northern region(sandy loam and clay loam) using input for climatic data , and data of class Apan evaporation.The results showed that data of pan evaporation class A can be relied on in simulating and calculation of evaporation from the soil surface, where the standards of statistics (IOA, R2) calculated on the basis of evaporation pan class A data are better for the wetting intervals (2,4, 8, 16 ) days compared with the values of those standards based on full climate data and both types of soil. The study also showed that the wetting intervals and their impact on evaporation from the soil surface and evaporation stages reasonably agree with the results of field experiments that have been made in this area.